1. Field of the Invention
This invention relates to gas lasers and to systems for maintaining the required volume of gas in a gas laser tube.
2. Background Art
U.S. Pat. No. 4,683,575 illustrates a gas fill system for a gas laser in which a gas metering chamber is opened and closed by a pair of solenoids. U.S. Pat. No. 4,815,100 illustrates a gas fill system in which a single solenoid opens and closes the metering chamber. The fill systems of both of the mentioned patents direct the gas directly from the reservoir to the metering chamber and then to the gas filled laser tube. U.S. Pat. No. 4,689,796 describes another system in which a gas entrapping material has its temperature controlled to control transfer of gas from the entrapping material to the gas filled laser tube according to the tube pressure which is monitored by monitoring the tube voltage.